Feeding device



March 13, 1945. R. LUTHI 2,37 7

FEEDING DEVICE Filed Dec. 1, 1942 3 Sheets-Sheet 1 a i ii 74 g z! 5 77 a? 4 w z? /4 7 9| 7/ lb 'Z? INVENTOR.

March 13, 1945. R. LUTHI 2,371,177

FEEDING DEVICE A TTOE/Vdxs March 13, 1945. R. LUTHI 2,371,177

FEEDING DEVICE Filed Dec. 1, 1942 3 Sheets-Sheet 3 F1 T A 5 A ATTOg/VEYQ Patented Mar. 13, 1945 FEEDING DEVICE Robert Luthi, Forest-Park, 111., assignor to. Ameri- .can Can Company, New York, N. Y., a corporation. of New Jersey Application December 1, 1942,.Serial No. 4'67 ,5.22

5 .Claims.

"The present invention relates to "a feeding device 'ior "a *container or can making machine in which container parts are produced from sheets "01f strips havingthe'container parts ar ranged in a multiple *row staggered layout and has particular reference to feeding the strips inapontinuous step-by-step fashion through a working "station in the machine in a manner which *compensates for the. space between adjacent strips inthe line and for'the staggered layout ofthe containerparts in the strips-sothat upon ente'ring the working station they will be prcperly located foran operationto be performed thereon. '-'Ihis is an improvement on the feeding device disclosed in United States Patent 2,280,823, issued April 28, "1942,10 J. Hansen.

"Inscm-epanmaking machines such as for example, strip feed presses or the *like'inwhich can parts arecutfromsheet metal strips by suitable die mechanism;considerable lost motion is often encounteredin idle or'nonproductive die movement between the 'feeding 'of strips. In most cases these: strips are 'form'ed'in' short lengths and usually at least .one or two strokes of the die' mechanism are lost'betweeneach strip as they are fed one after the otherinto thedie.

The greatest difficulty is encountered when ieeding'the .so-ca11ed.scroll shear strips which are usually cutlfrom a stagger rowlayout sheet which .gives .the strips .un'dulated' side edges. In such strip .the stagger .layout leaves .a greater amount of scrapstock atoneend of thestrip than at its .oppositeen'd. For fdoublerow strips in which two rows ofcan parts are .cut from one strip, ,the can parts are arranged in a stagger layout in the strip itself and two .canpartsare simultaneously cut out by .the die mechanism. This necessitates advancing the strip upon its initial entry into the ,diemechanism, through a strokeof differentalengthin order to bring the strip into proper registration withthe .dies.

Theinstant invention contemplates overcoming ithis .diifieulty 'by providing a :feeding device which will :compensate 'IfOI this different feeding zdistance atthe beginning 'of: a'strip feeding oper-- ation so that the strips may be fed successively into proper positionintothe: die mechanism.

An object therefore of the :invention is the provision of a strip feeding devicefor'a-can making machine wherein thewstrips'may be'fedsum cessivelyinto a working station ofthe machine while compensatingfor the stagger layout of the can parts in the strips and while properlylocating the strips :upon entering the workingastation for the 3 performance of an operation 1 thereon.

Another object is the provision'of 'such a feeding'device wherein apredetermined back orreturn stroke of a reciprocating feed bar is-utilized during :the 'step iby-step advancement of a strip, to advance the strip thedifierentrdistance required tomompensaterfor the stagger ilayoutof adjacent: strips andttoyproperly locate" the entering: strip at the workingstation.

Numerous other objects and advantages of the invention will be "apparent as it is better understood from the following 7 description, which, taken in connection with the accompanying drawings, discloses a preferred embodiment thereof.

Referring to thefidrawingsz Figural is-aside elevation of astripfeed press havingxa feeding device embodying theinstant invention, the view also including a Wiring diagram =of the electricapparatus used with the feeding device;

Fig. 2 is an enlarged sectional detail of the feeding device, with parts broken away;

Fig. :3 is a transverse section taken substantially along the line 3--3 in Fig. l, with parts broken away;

Fig. 4 is a longitudinal section taken substantially along'the line-44 in Fig. 3, with parts broken away;

Fig 5 is a transverse section takensubstan- .tially along the line 5-5 in Fig. 3, with parts sheets in which the canparts to-be formed are laid out in stagger row fashion. The strips are out along lines of severance which extend between one or more of the stagger rows and hence result in undulated side edges B. In the present case the drawings show a double row strip in which there are two rows of potential can part areas in each strip, the potential can part areas being arranged in staggered order as best shown in Fig. '7'.

The potential can part areas indicated by the letter C in Fig. 7 are equally spaced throughout the length of the strip and the center distance between such part areas is marked X. However, the lower (i. e., lower as to Figs. 6 to 9, inclusive) row of potential can part areas, as viewed in Fig. '1, is staggered or offset in relation to the upper row by a distance equal to one half X so that the can parts may be most economically out from the strip. Such a cutting of the strip leaves a scrap skeleton D (Fig. 6) with the least amount of waste material.

In cutting the can parts from the strip one can part is cut from each row, the two can parts being cut simultaneously. This is usually effected by a die mechanism having two diagonally spaced dies E; F (Fig. 8). Due to mechanical obstructions, such as the required thicknesses of the die walls and other protuberances, it is impossible to arrange these two dies E, F so that diagonally adjacent can parts can be cut from the strip simultaneously.

For best results this necessitates the spacing apart of the dies a longitudinal distance equal to one and one half times X which permits of the cutting of one can part from the upper row and another can part in the lower row one and one-half times the longitudinal distance X from the one in the upper row. By way of illustration the positions of these two can part areas are in- 'dicated by dotted lines lettered G and H in Fig. '7

The first can part to be cut from a strip upon its entrance into the die mechanism is the first or forward can part area in the lower row of the strip while the last out made on each strip takes out the last or rear can part area in the upper row as the strip leaves the die mechanism, the work moving toward the right. It will be understood that the terms upper and "lower rows are relative only as they appear in Figs. 6 to 9, inclusive, and do not designate an'upper or lower position in the machine.

Thus, clue to this stagger layout, the center of the first can part area C in the lower row of a strip A, is spaced inwardly from the front edge of the strip a distance U which is a greater distance than the distance (marked Y) the center of the first can part space in the upper row is spaced inwardly from the front edge of the strip. The difference between these distances is substantially equal to the amount of offset between the lower and the upper rows of can part areas,

i. e., approximately one-half of X. This same relation in reverse exists at the rear end of the strip.

In feeding double row strips through the die mechanism in a step-by-step fashion the distance the strip is advanced on each step is equal to the center distance X between the potential can part spaces or areas C in one row' of the strip. When the two offset rows in the strip are cut out simultaneously and the longitudinal distance between the centers of the dies E, F is equal to one and one halfX, the one half X difference between these two distances must be compensated for as a strip enters the die mechanism to properly located the scroll edge of the strip and the location of the potential can part area relative to the dies E, F. It is to this feature that the invention is particularly directed.

It will be understood that the space for the feeding elements between the back edge of one strip andthe front edge of a following strip being fed through the die mechanism, in end to end relation, permits of the required extra advancement of the following strip as the latter enters the die mechanism. When single row strips are fed through the apparatus, the instant invention is equally well adapted for advancing the strips a distance sufficient to compensate for the space between them so that any otherwise lost strokes of the die mechanism will be eliminated.

In the strip feed press and feed shown in the drawings, the strips A are supported on top of a table II (Figs. 1, 3, 4 and 5) which is secured to a bracket 12 bolted to a bed I3 of a frame I4 which constitutes the main frame of the strip feed press. Many of the press parts are inclined as shown so that a guide l6 formed along one edge of the table and constituting a track on which the strip rests, retains the strip for longitudinal movement. At the same time a top plate l1 secured to the guide prevents vertical displacement of the strip. The strips are placed upon the table in any suitable manner in time with the moving parts of the press, such as disclosed in the above mentioned Schoendelen patent.

The dies E, F of the die mechanism are located at one end of the table I l (at the right as viewed in Figs. 3 and 4). This die mechanism may be of any suitable conventional form such as one adapted to cut and draw can parts C, for example can ends, from the strips A, as the latter are fed into proper position.

Byway of example, the die mechanism includes the two dies E, F which are stationary and two cooperating punch members l9 which are mov able from above into and out of the dies. The dies are secured preferably to a bed plate 2! which is bolted to the bed of the press. The punch members are secured preferably to an inclined vertical slide 22 which operates in slideways 23 formed in the press frame [4. The slide is reciprocated in the usual manner in time with the other moving parts of the machine by way of connection with a drive shaft 25 which is journaled in bearings formed in the press frame. The shaft may be rotated in any suitable manner.

The strips are fed along the table II and are positioned between the die members for the can end cutting and forming operation, in a step-bystep or intermittent movement. For this purpose there is provided a feeding device which includes a longitudinally reciprocable main feed bar 3| which slides in a groove 32 formed in the table I! longitudinally thereof. The feed bar carries a plurality of spring held feed fingers 33 which are spaced apart at equal intervals along the bar and which may be depressed below the strip when the feed bar moves through a back ward or return stroke. These intervals are equal to the distance X (Fig. 7) between the centers of the potential can parts or ends C in the strips A to be fed. The fingers are disposed in the groove 32 alongside of the bar and move with it within the groove.

The main feed bar 3| is reciprocated by way of a link 36 (Figs. 3 and 4) the outer end of which is connected to an arm 31 adjusted in position and carried on the outer end of the feed bar. The arm is held in the desired position by locknuts ,precedingystripis the one inwhich the 2,8713 F38 threaded onto the end of: the :bar. The inner end of the'link is connectedto one arm of a bell crank lever 'til mounted-on a pivot pin fl carried :inthe feedsupport bracket I 2. The bellcrank lever *is connected throug'h a ssecond arm to the lower end Y ofan actuating rod 42 which extends up "toward the top-of the press 'and is attached to an eccentric disc 43 mounted on the outer end ofthe main'driveshaft fioi thexpress. Itis this 'driveconnection-that actuatesthe main feed bar '31 in time with the othen-moving partscf the press.

When a strip A is'placed 'upomthetable 1 I for feeding through the machine it depresses all of thefingers 3'3"withwhich it'engages. It is placed infront of the rear or-outermost finger, as-shown in "Fig. 6, and this finger is notdepressed. When "the feed bar *moves "forward through a ieeding stroke this rear 'or 'outer "finger engages behind the rear edge -off the-strip and'adva'nces it through 1 a single step bringing the strip into the position shown in'Fig.7. This doesn'ot advance thestr'ip farenoughto be acted onbut merely brings its forward edgecloselyndjacentthe die E of'the die mechanism.

During "this "same forward stroke of the .feed bar, its innermost ort'front finger 33 engages *against the back edge of the preceding strip A already positioned in 'the die mechanism and advances it from'theposition ShoWn'in'Fig. .6 to

thatshown in Fig. 7. This new-position of the last can end spaceis disposedover the die F. On the back or returnstroke of the main feed bar 3| both advanced strips remain stationary for apart .of the movement .and the depressed ,feed .fingers "33 pass under the strips. During this return stroke of the 'feed bar'the last can end in the forward strip'is blanked .out and formed by the die F but die E passes into the 'spacebetweenthe strips without performing any operation. After this operatiomthe scrap skeleton of the forward strip is ejected from thepress by a'suitable ejector device such as vis usual in the 7 present type'cf presses. This ejection preferably takes vplace .immediately after the punch and die have performed their work.

.Itisnearlthe end of the first return stroke of theifeed bar 3'! that the rear or succeeding strip is again advanced through a short stroke which is substantially equal to one-half of the distance X. This compensates "for the difference between the dimensions U and Yiherein'before mentioned as incident to the staggered layout of can part areas and the resulting spacing inwardlyirom the leading edge of the strip.

Thisreturn feed barand short stroke advancement oi the strip, brings .its forward edge into partialposition .over thedieE, as shown in Fig.

.8. The short stroke shifting of the stripinto-this position takesplace while the punch elements H! of the .die .mechanism are traveling through an up-stroke. l

The return .ieedstroke with itssattendant short stroke advancement of the strip. is brought about by an auxiliary 'feedbar 51 (Figs. .3, 4, 5 and 8) which is located alongside oi the main :feed bar 3| and is in spaced and parallel relation there,- with. The auxiliary "feed bar 5| slides in a groove 52 formed in the table II and carries a depressiblespringheld feed finger or dog 53.

The outer orrear end of theauxiliaryieedbar -51 'is connected by a link SEto'the'upper end of an-uprightleVer-BB which iSlTIOlll'l'tBd on a'pivot pin 5'! carried inahracke'ti'B"boltedtothe'bot- =tom-of the table I l. Thelower end of the lever is connected to a slide rod 6| which carries a slide-sleeve (see also Fig. 2) on-which a'spring pressed sliding element 63 operates. The said sliding element is secured to the lower end of the-arm 31 which,'it-will be'recalled, is movable with "the main "feed bar 3 I. I

. The outer'end of the slide rod 6| carries a yieldable, "tubular, actuating shoe 55 which is held in "place against the outer end of the slide sleeve "6'2 by a compression spring 66 which surrounds theshoe. The outer end of the spring'is held in place 'by a Washer 61 which engages 'against apairof locknuts 68 threaded ontoth e slide rod. The nuts are adjustable to regulate the pressure "of the "spring 66.

In-normal position, the'auxiliary feed bar 5! restsin theforward end of its groove 52, as shown in l ign' i. In this position, "the slide'rod "6| is so disposedthat the'ac't-uating shoe 65is just beyond thereach o'fthe sliding element 63 when 1151's in its "rearmost position, so that the sliding element is disposed 'to'movealong' the rod 'with movement of the main feed'bar 3! without any effect on the rod'oron the auxiliary feed 'bar which it actuates.

Just prior to the "first return stroke of. the main feed 'bar 31, the auxiliary feed bar 5| is shiftedormovedrearwardlyand is not in its normal position. Accordingly at the time of this first rearward stroke of the feed bar, the auxiliaryieeddog tii isjust in back of'the rear edge ofthe strip (Fig. "7) and the slide rod 6| is disposed forwardly 'sothat the actuating shoe 65 is in the-path'o'f travel .oithe slidingelement on the return "stroke of the main feed v.bar.

TI'heshiiting of "theauxiliary feed bar Z5! out ofits'norma'l position and-the shifting of the slide rod '61 into such position is brought about by a solenoid "Tl ,(Fig. 4) which is "securedto' an extension "H! o'f'the feed support bracket 1 2. The solenoi'cl is formed with "a freely movable core 13 which 'is'not under compression of a spring housed within thesolenoidas is usual in such "solenoids. Theouter-endof the core is connected by a'link 14 to "the'auxiliary feed bar lever 56 'as shown "in Fig. I 4.

The 'solenoidql is maintained normallyin a 'deenergized condition. It is "energized by the closing of-a normally open toggle switch 16 (Fig. l) which is secur'ed to the side of :the press frame 14. One side of the switch is connected by .a

erator T9 which constitutes the main source of electric energy. The generator is connected by a"wire 8! to a'manuallyfoperated service switch tzywhich switch is connectedby a wire 83 to the solenoid.

Closing of the toggle switch I6 is eiiected in time with the feeding of the strips .A, by'an operating lug 85 which is engageable against a movable element *36 of the switch 16. The lug is -formed 'on the'side of 'agear 8! mounted on ashort shaft88 journaled in 'a suitable bearing iormedin the press frame M. The gear meshes wi'thand'is rotated by'a pinion which is carried on themain-drive'shaft 25 adjacent-the eccentric disc 43. The gear ratio is such asto cause one complete rotation of the gear '81 for each feeding cycleofa singlestrip. I

Hence the switch parts are so timed that just prior-to the first returnstroke of the main feed bar 31,

elemental; of the switch "16 and thus closes the the mg 85 engages against'themovable switch. When this switch 16 and the service switch 82 are both closed, the solenoid circuit is established. Hence electric energy from the generator l9 flows along the circuit and through the solenoid and thus energizes the solenoid.

The energizing of the solenoid is of momentary duration since the lug passes beyond the switch element and thus permits the switch to open again but it is of sufficient duration to propel the core 13 outwardly and thus shift the auxiliary feed bar into operative position as mentioned above. The feed bar and the solenoid core remain in this shifted position when the solenoid is deenergized by the opening of the switch 16.

With the auxiliary feed bar 5| in this shifted position, the sliding element 63 upon completion of the return strokeof the main feed bar 3|, engages the actuating shoe 65 on the slide rod BI and thus draws the slide rod rearwardly with the feed bar. This rocks the lever 56 and hence again pushes the auxiliary feed bar 5| forward in its groove 52 into its normal position. Such a forward movement of the auxiliary feed bar brings its feed dog 53 into engagement with the rear edge of the strip A and pushes the strip forward the required distance to make up the difference between the strip dimensions U and Y. This operation is performed while the main feed bar 3| is moving back through its first return stroke. The spring 65 adjacent the actuating shoe 65 provides a yielding engagement of the feed dog against the strip and thus prevents nicking of the strip. This movement of the strip serves to advance its forward end into the position shown in Fig. 8. The forward movement of the auxiliary feed bar also returns the solenoid core 13 to its original position within the solenoid.

As soon as the main feed bar 3! reaches the outer limit or end of its first return stroke, its second feed finger 33 snaps up in back of the strip and the bar immediately moves forward on its second forward stroke. This second stroke of the main feed bar advances the single strip further into the die mechanism and into the position shown in Fig. 9 and properly locates the forward end of the strip over the die E in readiness for the first cutting and formingoperation for the new strip. Only one can end C is cut from the strip while it is in this position and the die F does no work for that stroke.

During this second forward stroke and through all of the remaining strokes of the main feed bar 3!, the auxiliary feed bar 5| remains at rest in normal osition in its groove 52. The actuating shoe 65 on the slide rod Bl also remains in its outwardly shifted position where it is out of the path of travel of the slider 63 on the main feed bar 3!. Hence there is only one forward stroke of the auxiliary feed bar for each strip A and this is effected on the first return stroke of the main feed bar for a new strip.

It is thought that the invention and many of its attendant advantages will be understood from the foregoing description, and it will be apparent that, various changes may be made in the form, construction and arrangement of the parts without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the form hereinbefore described being merely a preferred embodiment thereof.

I claim:

1. In a device for feeding strips of sheet material in a continuous procession along a predetermined path of travel to position successive portions of the strip at a working station,'the combination of a main feed bar reciprocable through a, feeding stroke and a return stroke, means on said feed bar for successively engaging behind the feeding edge of the strip to advance the strip in a step-by-step manner, and means connected to said feed bar and rendered effective by the bar on its return stroke for engaging the feeding edge of the strip to advance the strip an increased forward distance as it initially enters the working station to locate the leading edge of the strip in a predetermined position for operation thereon at the working station.

2. In a device for feeding strips of sheet material in a continuous procession along a predetermined path of travel to position successive portions of the strip at a working station, the combination of a main feed bar reciprocable through a feeding stroke and a return stroke, a plurality of feed dogs spaced at equal intervals along said feed bar for successively engaging behind the rear edge of the strip to advance the strip in a stepby-step manner, an auxiliary feed bar freely slidable adjacent said main feed bar, a feed dog mounted on said auxiliary feed bar, and means movable with said main feed bar on a return stroke for shifting said auxiliary feed bar to bring its feed dog into engagement with the feeding edge of the strip and to advance the strip an extra distance as it initially enters the working station to locate its leading end portion in a predetermined position at the working station.

3. In a device for feeding strips of sheet material in a continuous procession along a predetermined path of travel to position successive por-' tions of the strip at a working station, the combination of a main feed bar reciprocable through a feeding stroke and a return stroke, a plurality of feed dogs spaced at equal intervals along said feed bar for successively engaging behind the rear edge of the strip to advance the strip in a step-by-step manner, an auxiliary feed bar freely slidable alongside of said main feed bar, a feed dog mounted on said auxiliary feed bar, a rocker lever connecting with said auxiliary feed bar, a

slide rod having an actuating head carried on said lever, and a slide member movable along said rod and mounted on said main feed bar for advancing said auxiliary feed bar during an initial strip feeding return stroke of said main feed bar to bring the auxiliary feed dog into engagement with the feeding edge of the strip and to advance the strip as it initially enters the working station to bring its leading end portion into a predetermined position at the working station.

4. In a device for feeding strips of sheet material in a continuous procession along a predetermined path of travel to position successive portions of the strip at a working station, the combination of a reciprocating main feed bar having a feeding stroke and a return stroke, a plurality of feed dogs spaced at equal intervals along said feed bar for successively engaging behind the rear edge of the strip to advance the strip in a stepby-step movement, an auxiliary feed bar mounted for free sliding movement adjacent said main feed bar, a feed dog carriedby said auxiliary feed bar, means for sliding said auxiliary feed bar relative to said main feed bar to set the auxiliary feed bar in an operable position, and means mov able with said main feed bar for shifting said set auxiliary feed bar to bring its feed dog into engagement with the rear edge of said strip and to further advance the strip an added distance during a return stroke of said main feed bar whereby the leading front portion of a strip initially brought into said working station is in proper position to be operated on at that station.

5. In a device for feeding strips of sheet material in a continuous procession along a predetermined path of travel to position successive portions of the strip at a working station, the combination of a reciprocatingmain feed bar having a feeding stroke and a return stroke, a plurality of feed dogs spaced at equal intervals along said feed bar for successively engaging behind the rear edge of the strip to advance the strip in a step-bystep movement, an auxiliary feed bar having free sliding movement adjacent said main feed bar, a feed dog carried by said auxiliary feed bar, a rocker lever connecting with said auxiliary feed bar, an electric solenoid having a movable core movable with said main feed bar and along said rod for shifting said set auxiliary feed bar to bring its feed dog into engagement with the rear edge of the strip and to further advance the strip an added distance during a return stroke of said main feed bar whereby the leading portion of a strip initially brought into said working station is' in proper position to be operated on at that station.

ROBERT LUTHI. 

